The invention is based on a measuring instrument for contactless detection of an angle of rotation. DE-OS 196 34 381.3 has disclosed a sensor which is disposed in three superposed planes. The rotor constitutes the middle plane, wherein it is comprised of the supporting plate for a permanent magnet. The supporting plate itself is comprised of magnetically nonconductive material so that the magnetic flux travels via the two other planes, i.e. the stator, and is dispersed with the aid of two spacers which are disposed between the two planes of the stator. The shaft or the projection of a shaft that is attached to the rotor has no influence on the magnetic flux. With this sensor, a relatively large angular range can in fact be measured without a change of sign, but it is relatively large in terms of the axial direction due to being constructed of three parallel planes.
The measuring instrument for contactless detection of an angle of rotation according to the invention has the advantage over the prior art that the sensor has a relatively small size in the axial direction. It is comprised of only two planes. The supporting plates of the permanent magnet which represents the rotor is simultaneously also used to convey the magnetic flux. Furthermore, the shaft or axle supporting the rotor is included in the conduction of the magnetic flux, as a result of which additional magnetic flux conducting pars are rendered unnecessary. Furthermore, this design reduces the number of parts and the assembly costs involved with them.
Due to its simple design, the sensor can, for a relatively low assembly cost, be integrated into various systems, e.g. a throttle measuring device, a pedal module for a gas pedal travel sensor or can be used as an independent sensor in throttle valve transmitters or a body spring compression device.
Advantageous modifications and improvements of the measuring instrument disclosed in claim 1 are possible by means of the steps taken in the dependent claims.